Patent document 1 describes a technique which, in a hybrid vehicle in which an engine and a motor are equipped as power sources of the vehicle, improves a control stability of the idling revolution speed control by enabling a switching between an engine idling mode in which an idling speed revolution speed control is carried out through the engine and a motor idling mode in which the idling revolution speed control is carried out through the motor in accordance with a charged state (SOC) of the battery, during an idling drive.
Incidentally, during the idling drive in the cold state in which a warm-up of the engine is not completed, an exhaust rise temperature control to promote the warm up of the engine by raising an exhaust gas temperature of the engine in order to activate, at an early timing, a catalyst installed in an exhaust system of the engine is carried out.
One of the exhaust rise temperature controls includes a known technique to raise the exhaust temperature by reducing a combustion efficiency by retarding a firing timing of the engine (an ignition timing through a spark plug).